Question

Which of the following salts will give highest pH in water?

• A. $\text{CuS}{\text{O}}_4$
• B. KCl
• C. $\text{N}{\text{a}}_2\text{C}{\text{O}}_3$
• D. NaCl

Answer 1

Answer: (C)

$\text{N}{\text{a}}_2\text{C}{\text{O}}_3$ will give highest pH in water because it is a salt of strong base and weak acid so aqueous solution is alkaline with pH more than 7. KCl, & NaCl are salts of strong acid & strong base so aqueous solution is neutral & pH is 7. $\text{CuS}{\text{O}}_4$ is a salt of strong acid &weak base so aqueous solution is acidic with pH less than 7.